Changes

316 bytes added , 14:08, 3 April 2023

→‎00FF 2A 55 Meter Data: Changed data tags based on discovery using IWR

|1010

|}

----Of particular note is the difference between versions 1-4 and version 5. In version 5 there are two bits [11] that do not respect the start/stop bit checks of the prior versions. The older protocol expects a 0 start bit, ~~bit~~ 8 data bits and a 1 stop bit. By violating two consecutive start bits the older versions of ~~Gridstream~~ GridStream ignore version 5 even if they have the same CRC Adder! This appears to be a way to add backwards compatibility to newer versions of ~~Gridstream~~GridStream.

{| class="wikitable"

|+Header for Gridstream

! colspan="32" |Header v1 - v4

! rowspan="3" |

! colspan="32" |Header v5

|-

!0x00

!0xFF (10 bit)

~~!0x2A~~

!0x00

!0xFF (11 bit)

~~!0x2A~~

|-

|0 '''00000000''' 1

|0 '''11111111''' 1

~~|0 '''00101010''' 1~~

|0 '''00000000''' 1

|[11] '''11111111''' 1

~~|0 '''00101010''' 1~~

|}

----Using GNU Radio it was found that shortening the Sync requirements a bit and incorporating part of the header leads to the cleanest data for further downstream processing. The modified sync ~~shown~~ in 8 bit chunks is shown below. These two sync's are both loaded into the '''PDU Align''' block and if either one is matched the full packet is passed downstream.

{| class="wikitable"

|+Sync Word used with GNURadiofor v4

!0xAA

!0x00

!0x5F

!0xF

|-

|10101010

|00000000

|01011111

|1111

|}

{| class="wikitable"

|+Sync Word used with GNURadio for v5

!0xAA

!~~0xA0~~0x00!~~0x05~~0x7F!~~0xFF~~0x1F

|-

|10101010

|~~10101010~~00000000|~~10101010~~01111111|~~10100000|00000101|11111111~~11111

|}

~~The final byte of the sync (0x2A) along with it's start and stop bits are discarded as part of the processing.~~

----<br />

====~~Type, Length~~ Packet Types and ~~Sub Type~~Structures====----Data is shown in Hexadecimal unless stated otherwise So far only two types of packets have been observed, a 0x55 and a 0xD5 packet. Multiple lengths and SubTypes of these exist, a few are listed below.

{| class="wikitable"

|+

!

!Start of

Frame

!Type

!Sub Type

!Sequence

! colspan="2" |Packets Purpose

|-

!

|00FF

|00

|81 or 85

|1 Byte

| colspan="2" |Report Power Usage (Device Control Word DCW)

|-

!

|00FF

|01

|81 or 85

|1 Byte

| colspan="2" |Report Power Usage (Device Control Word DCW)

|-

!

|00FF

|02

|81 or 85

|1 Byte

| colspan="2" |Report Power Usage (Device Control Word DCW)

|-

!

|00FF

|03

|81 or 85

|1 Byte

| colspan="2" |Report Power Usage (Device Control Word DCW)

|-

!

!Start of

Frame

!Type

!Sub Type

!Length

!~~SubType~~Unknown

!Packets Purpose

|-

!1

|~~0x55~~00FF|~~0x0023~~2A|~~0x30~~55|0023|30

|Report up-time and other unknown data

|-

!2

|~~0x55~~00FF|~~0x0028~~2A|~~0x30~~D5|0047|51|Includes Epoch and Uptime

|-

!3

|~~0xD5~~00FF|~~0x0011~~2A|~~0x21~~D5|00FD|-!4~~|0xD5|0x0011|0x22~~||-!5~~|0xD5|0x0011|0x29~~||-!6~~|0xD5|0x0016|0x21~~||-!8~~|0xD5|0x0016|0x29~~||-!7~~|0xD5|0x0017|0x21~~||-!9~~|0xD5|0x0017|0x29~~||-~~!10|0xD5|0x001C|0x21~~||-~~!11|0xD5|0x001C|0x29~~||-~~!12|0xD5|0x001D|0x29~~||-~~!13|0xD5|0x0047|0x51~~||-~~!14|0xD5|0x00FD|0xC0~~C0

|

|}

----

====~~0x55~~ 00FF 2A 55 Meter Data====

The data below was captured from the same meter (F0EE36DB) and shows some of the values that can change with each transmission. Different meters have different fixed data and some of the data changes less frequently as well.

{| class="wikitable"

0x55 Captured packets from Meter F0EE36DB (Oncor)

! rowspan="3" |Pkt

!0

!1

!2

!16

|-

! colspan="34" |Not part of CRC calc! colspan="119" |DataPacket! colspan="23" |Trailing 6 Bytes!

|-

!~~Header~~Start of Frame

!Type

!SubType

!Length

!~~SubType~~Unknown

!Unknown

!WAN Address

|-

!1

|~~00FF2A~~00FF|2A

|55

|0023

|-

!2

|~~00FF2A~~00FF|2A

|55

|0023

|-

!3

|~~00FF2A~~00FF|2A

|55

|0023

|-

!4

|~~00FF2A~~00FF|2A

|55

|0023

|-

!5

|~~00FF2A~~00FF|2A

|55

|0023

|-

!6

|~~00FF2A~~00FF|2A

|55

|0023

|-

!7

|~~00FF2A~~00FF|2A

|55

|0023

|-

!8

|~~00FF2A~~00FF|2A

|55

|0023

|-

!9

|~~00FF2A~~00FF|2A

|55

|0023

|-

!10

|~~00FF2A~~00FF|2A

|55

|0023

|+0x55 Captured packets from Meter 5021D005 (Coserv)

! rowspan="3" |Pkt

!0

!1

!2

!16

|-

! colspan="34" |Not part of CRC calc! colspan="119" |DataPacket! colspan="23" |Trailing 6 Bytes!

|-

!~~Header~~Start of Frame

!Type

!SubType

!Length

!~~SubType~~Unknown

!Unknown

!WAN Address

|-

!1

|~~00FF2A~~00FF|2A

|55

|0023

|-

!2

|~~00FF2A~~00FF|2A

|55

|0023

|-

!3

|~~00FF2A~~00FF|2A

|55

|0023

|-

!4

|~~00FF2A~~00FF|2A

|55

|0023

|-

!5

|~~00FF2A~~00FF|2A

|55

|0023

|04

|-

! colspan="1718" |Power restored after an outage

|-

!6

|~~00FF2A~~00FF|2A

|55

|0023

|-

!7

|~~00FF2A~~00FF|2A

|55

|0023

|-

!8

|~~00FF2A~~00FF|2A

|55

|0023

|-

!9

|~~00FF2A~~00FF|2A

|55

|0023

|-

!10

|~~00FF2A~~00FF|2A

|55

|0023

----

====~~0xD5~~ 00FF 2A D5 Meter Data====

There appear to be multiple packet lengths and styles for the 0xD5 packet. Some samples shown below, [https://wiki.recessim.com/w/images/9/9e/D5-Packets-Table-F03B9FFB.txt download as a txt file].

{| class="wikitable"

! rowspan="3" |Pkt

!1

!

!2

!3

! colspan="2" |

|-

! colspan="34" |Not part of CRC calc

! colspan="9" |CRC'd Data

!CRC

! colspan="2" |

|-

!~~Header~~Start of Frame

!Type

!SubType

!Length

!~~SubType~~Unknown

!DST Meter

!SRC Meter

|-

|1